An important indicator of animal health is the body composition of the animal. An unhealthy diet and/or an unhealthy lifestyle can result in the animal having an unhealthy proportion of body fat, particularly in relation to lean muscle in the body. It is thought that a body fat amount in excess of 30% by weight indicates that the animal is unhealthy, particularly if the amount of body fat is in excess of 35% by weight.
Animals, particularly companion animals (e.g., dogs and cats), may weigh more than their ideal body weight. Having an excess of adipose tissue, these animals may be clinically diagnosed as, e.g., “fat”, “overweight”, or “obese” and, as such, are more likely to suffer from associated physical disorders such as arthritis, heart disease, respiratory disease, diabetes, bladder cancer, hypothyroidism, joint disease and/or pancreatitis.
Attempts to prevent or reduce the amount of excess adipose tissue on companion animals typically include dietary restriction and exercise. Indeed, many “low” or “reduced” calorie foods for overweight companion animals have been developed and are commercially available for the control of calorie intake, prevention of weight gain, or for the promotion of weight loss. One strategy in weight loss involves high protein diets with high protein to calorie ratios in order to reduce the amount of body fat in humans. A similar approach has been used in companion animal products. High protein diets have proven to be effective in weight loss in cats; however high protein foods have had mixed results when applied to canine weight management programs. Treatment strategies also include increasing the fiber and/or protein content while reducing the fat in the food. Depending on the fiber source, the fiber can induce satiety via gut distention or through feedback mechanisms (e.g., GLP-1). Fiber can be effective in reducing the digestibility of food resulting in a lower availability of high calorie nutrient components (i.e., fat and carbohydrates).
Generally, companion animals such as canines and felines weighing more than 15% of their ideal body weight are considered overweight or obese. Overweight animals generally have an excess of body adipose tissue. The most common cause of an animal being overweight is an over consumption of food that results in an excess intake of calories. However, there are other factors that can increase an animal's chances for being overweight, e.g., lifestyle, health, eating habits, breed, spaying, and neutering. Also, the incidence of animals becoming overweight generally increases with age due to a general decrease in metabolic rate and in physical activity. Surveys estimate that 25% of canines in the United States that visit veterinary clinics are fat to the point of being obese.
Losing weight or maintaining weight, particularly for a companion animal, is difficult. It is necessary to modulate the caloric intake of the animal. Modulating the amount of adipose tissue on a companion animal, including preventing an animal from becoming overweight or treating a fat animal to reduce the amount of adipose tissue on the animal, is also difficult. An effective way to prevent an animal from becoming fat or to reduce the amount of fat on an animal is with dietary restriction and exercise. However, it is often difficult to ensure compliance with diet and exercise programs.
Given the problems with current methods for losing weight or maintaining weight, there is a continuing need for new methods and compositions useful for maintaining or promoting a healthy body composition, wherein maintaining or promoting a healthy body composition comprises controlling the animal's weight, for example, loss of weight or body fat, or increased percentage of lean muscle mass, in a companion animal and, in particular, for food compositions effective in these conditions.